xref: /openbmc/linux/arch/parisc/include/asm/pgtable.h (revision 8dd3cdea)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _PARISC_PGTABLE_H
3 #define _PARISC_PGTABLE_H
4 
5 #include <asm/page.h>
6 
7 #if CONFIG_PGTABLE_LEVELS == 3
8 #include <asm-generic/pgtable-nopud.h>
9 #elif CONFIG_PGTABLE_LEVELS == 2
10 #include <asm-generic/pgtable-nopmd.h>
11 #endif
12 
13 #include <asm/fixmap.h>
14 
15 #ifndef __ASSEMBLY__
16 /*
17  * we simulate an x86-style page table for the linux mm code
18  */
19 
20 #include <linux/bitops.h>
21 #include <linux/spinlock.h>
22 #include <linux/mm_types.h>
23 #include <asm/processor.h>
24 #include <asm/cache.h>
25 
26 /*
27  * kern_addr_valid(ADDR) tests if ADDR is pointing to valid kernel
28  * memory.  For the return value to be meaningful, ADDR must be >=
29  * PAGE_OFFSET.  This operation can be relatively expensive (e.g.,
30  * require a hash-, or multi-level tree-lookup or something of that
31  * sort) but it guarantees to return TRUE only if accessing the page
32  * at that address does not cause an error.  Note that there may be
33  * addresses for which kern_addr_valid() returns FALSE even though an
34  * access would not cause an error (e.g., this is typically true for
35  * memory mapped I/O regions.
36  *
37  * XXX Need to implement this for parisc.
38  */
39 #define kern_addr_valid(addr)	(1)
40 
41 /* This is for the serialization of PxTLB broadcasts. At least on the N class
42  * systems, only one PxTLB inter processor broadcast can be active at any one
43  * time on the Merced bus. */
44 extern spinlock_t pa_tlb_flush_lock;
45 #if defined(CONFIG_64BIT) && defined(CONFIG_SMP)
46 extern int pa_serialize_tlb_flushes;
47 #else
48 #define pa_serialize_tlb_flushes        (0)
49 #endif
50 
51 #define purge_tlb_start(flags)  do { \
52 	if (pa_serialize_tlb_flushes)	\
53 		spin_lock_irqsave(&pa_tlb_flush_lock, flags); \
54 	else \
55 		local_irq_save(flags);	\
56 	} while (0)
57 #define purge_tlb_end(flags)	do { \
58 	if (pa_serialize_tlb_flushes)	\
59 		spin_unlock_irqrestore(&pa_tlb_flush_lock, flags); \
60 	else \
61 		local_irq_restore(flags); \
62 	} while (0)
63 
64 /* Purge data and instruction TLB entries. The TLB purge instructions
65  * are slow on SMP machines since the purge must be broadcast to all CPUs.
66  */
67 
68 static inline void purge_tlb_entries(struct mm_struct *mm, unsigned long addr)
69 {
70 	unsigned long flags;
71 
72 	purge_tlb_start(flags);
73 	mtsp(mm->context.space_id, SR_TEMP1);
74 	pdtlb(SR_TEMP1, addr);
75 	pitlb(SR_TEMP1, addr);
76 	purge_tlb_end(flags);
77 }
78 
79 extern void __update_cache(pte_t pte);
80 
81 /* Certain architectures need to do special things when PTEs
82  * within a page table are directly modified.  Thus, the following
83  * hook is made available.
84  */
85 #define set_pte(pteptr, pteval)			\
86 	do {					\
87 		*(pteptr) = (pteval);		\
88 		mb();				\
89 	} while(0)
90 
91 #define set_pte_at(mm, addr, pteptr, pteval)	\
92 	do {					\
93 		if (pte_present(pteval) &&	\
94 		    pte_user(pteval))		\
95 			__update_cache(pteval);	\
96 		*(pteptr) = (pteval);		\
97 		purge_tlb_entries(mm, addr);	\
98 	} while (0)
99 
100 #endif /* !__ASSEMBLY__ */
101 
102 #define pte_ERROR(e) \
103 	printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
104 #if CONFIG_PGTABLE_LEVELS == 3
105 #define pmd_ERROR(e) \
106 	printk("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, (unsigned long)pmd_val(e))
107 #endif
108 #define pgd_ERROR(e) \
109 	printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, (unsigned long)pgd_val(e))
110 
111 /* This is the size of the initially mapped kernel memory */
112 #if defined(CONFIG_64BIT)
113 #define KERNEL_INITIAL_ORDER	26	/* 1<<26 = 64MB */
114 #else
115 #define KERNEL_INITIAL_ORDER	25	/* 1<<25 = 32MB */
116 #endif
117 #define KERNEL_INITIAL_SIZE	(1 << KERNEL_INITIAL_ORDER)
118 
119 #if CONFIG_PGTABLE_LEVELS == 3
120 #define PMD_TABLE_ORDER	1
121 #define PGD_ORDER	0
122 #else
123 #define PGD_ORDER	1
124 #endif
125 
126 /* Definitions for 3rd level (we use PLD here for Page Lower directory
127  * because PTE_SHIFT is used lower down to mean shift that has to be
128  * done to get usable bits out of the PTE) */
129 #define PLD_SHIFT	PAGE_SHIFT
130 #define PLD_SIZE	PAGE_SIZE
131 #define BITS_PER_PTE	(PAGE_SHIFT - BITS_PER_PTE_ENTRY)
132 #define PTRS_PER_PTE    (1UL << BITS_PER_PTE)
133 
134 /* Definitions for 2nd level */
135 #if CONFIG_PGTABLE_LEVELS == 3
136 #define PMD_SHIFT       (PLD_SHIFT + BITS_PER_PTE)
137 #define PMD_SIZE	(1UL << PMD_SHIFT)
138 #define PMD_MASK	(~(PMD_SIZE-1))
139 #define BITS_PER_PMD	(PAGE_SHIFT + PMD_TABLE_ORDER - BITS_PER_PMD_ENTRY)
140 #define PTRS_PER_PMD    (1UL << BITS_PER_PMD)
141 #else
142 #define BITS_PER_PMD	0
143 #endif
144 
145 /* Definitions for 1st level */
146 #define PGDIR_SHIFT	(PLD_SHIFT + BITS_PER_PTE + BITS_PER_PMD)
147 #if (PGDIR_SHIFT + PAGE_SHIFT + PGD_ORDER - BITS_PER_PGD_ENTRY) > BITS_PER_LONG
148 #define BITS_PER_PGD	(BITS_PER_LONG - PGDIR_SHIFT)
149 #else
150 #define BITS_PER_PGD	(PAGE_SHIFT + PGD_ORDER - BITS_PER_PGD_ENTRY)
151 #endif
152 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
153 #define PGDIR_MASK	(~(PGDIR_SIZE-1))
154 #define PTRS_PER_PGD    (1UL << BITS_PER_PGD)
155 #define USER_PTRS_PER_PGD       PTRS_PER_PGD
156 
157 #ifdef CONFIG_64BIT
158 #define MAX_ADDRBITS	(PGDIR_SHIFT + BITS_PER_PGD)
159 #define MAX_ADDRESS	(1UL << MAX_ADDRBITS)
160 #define SPACEID_SHIFT	(MAX_ADDRBITS - 32)
161 #else
162 #define MAX_ADDRBITS	(BITS_PER_LONG)
163 #define MAX_ADDRESS	(1UL << MAX_ADDRBITS)
164 #define SPACEID_SHIFT	0
165 #endif
166 
167 /* This calculates the number of initial pages we need for the initial
168  * page tables */
169 #if (KERNEL_INITIAL_ORDER) >= (PMD_SHIFT)
170 # define PT_INITIAL	(1 << (KERNEL_INITIAL_ORDER - PMD_SHIFT))
171 #else
172 # define PT_INITIAL	(1)  /* all initial PTEs fit into one page */
173 #endif
174 
175 /*
176  * pgd entries used up by user/kernel:
177  */
178 
179 /* NB: The tlb miss handlers make certain assumptions about the order */
180 /*     of the following bits, so be careful (One example, bits 25-31  */
181 /*     are moved together in one instruction).                        */
182 
183 #define _PAGE_READ_BIT     31   /* (0x001) read access allowed */
184 #define _PAGE_WRITE_BIT    30   /* (0x002) write access allowed */
185 #define _PAGE_EXEC_BIT     29   /* (0x004) execute access allowed */
186 #define _PAGE_GATEWAY_BIT  28   /* (0x008) privilege promotion allowed */
187 #define _PAGE_DMB_BIT      27   /* (0x010) Data Memory Break enable (B bit) */
188 #define _PAGE_DIRTY_BIT    26   /* (0x020) Page Dirty (D bit) */
189 #define _PAGE_REFTRAP_BIT  25   /* (0x040) Page Ref. Trap enable (T bit) */
190 #define _PAGE_NO_CACHE_BIT 24   /* (0x080) Uncached Page (U bit) */
191 #define _PAGE_ACCESSED_BIT 23   /* (0x100) Software: Page Accessed */
192 #define _PAGE_PRESENT_BIT  22   /* (0x200) Software: translation valid */
193 #define _PAGE_HPAGE_BIT    21   /* (0x400) Software: Huge Page */
194 #define _PAGE_USER_BIT     20   /* (0x800) Software: User accessible page */
195 
196 /* N.B. The bits are defined in terms of a 32 bit word above, so the */
197 /*      following macro is ok for both 32 and 64 bit.                */
198 
199 #define xlate_pabit(x) (31 - x)
200 
201 /* this defines the shift to the usable bits in the PTE it is set so
202  * that the valid bits _PAGE_PRESENT_BIT and _PAGE_USER_BIT are set
203  * to zero */
204 #define PTE_SHIFT	   	xlate_pabit(_PAGE_USER_BIT)
205 
206 /* PFN_PTE_SHIFT defines the shift of a PTE value to access the PFN field */
207 #define PFN_PTE_SHIFT		12
208 
209 #define _PAGE_READ     (1 << xlate_pabit(_PAGE_READ_BIT))
210 #define _PAGE_WRITE    (1 << xlate_pabit(_PAGE_WRITE_BIT))
211 #define _PAGE_RW       (_PAGE_READ | _PAGE_WRITE)
212 #define _PAGE_EXEC     (1 << xlate_pabit(_PAGE_EXEC_BIT))
213 #define _PAGE_GATEWAY  (1 << xlate_pabit(_PAGE_GATEWAY_BIT))
214 #define _PAGE_DMB      (1 << xlate_pabit(_PAGE_DMB_BIT))
215 #define _PAGE_DIRTY    (1 << xlate_pabit(_PAGE_DIRTY_BIT))
216 #define _PAGE_REFTRAP  (1 << xlate_pabit(_PAGE_REFTRAP_BIT))
217 #define _PAGE_NO_CACHE (1 << xlate_pabit(_PAGE_NO_CACHE_BIT))
218 #define _PAGE_ACCESSED (1 << xlate_pabit(_PAGE_ACCESSED_BIT))
219 #define _PAGE_PRESENT  (1 << xlate_pabit(_PAGE_PRESENT_BIT))
220 #define _PAGE_HUGE     (1 << xlate_pabit(_PAGE_HPAGE_BIT))
221 #define _PAGE_USER     (1 << xlate_pabit(_PAGE_USER_BIT))
222 #define _PAGE_SPECIAL  (_PAGE_DMB)
223 
224 #define _PAGE_TABLE	(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | _PAGE_DIRTY | _PAGE_ACCESSED)
225 #define _PAGE_CHG_MASK	(PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY | _PAGE_SPECIAL)
226 #define _PAGE_KERNEL_RO	(_PAGE_PRESENT | _PAGE_READ | _PAGE_DIRTY | _PAGE_ACCESSED)
227 #define _PAGE_KERNEL_EXEC	(_PAGE_KERNEL_RO | _PAGE_EXEC)
228 #define _PAGE_KERNEL_RWX	(_PAGE_KERNEL_EXEC | _PAGE_WRITE)
229 #define _PAGE_KERNEL		(_PAGE_KERNEL_RO | _PAGE_WRITE)
230 
231 /* The pgd/pmd contains a ptr (in phys addr space); since all pgds/pmds
232  * are page-aligned, we don't care about the PAGE_OFFSET bits, except
233  * for a few meta-information bits, so we shift the address to be
234  * able to effectively address 40/42/44-bits of physical address space
235  * depending on 4k/16k/64k PAGE_SIZE */
236 #define _PxD_PRESENT_BIT   31
237 #define _PxD_VALID_BIT     30
238 
239 #define PxD_FLAG_PRESENT  (1 << xlate_pabit(_PxD_PRESENT_BIT))
240 #define PxD_FLAG_VALID    (1 << xlate_pabit(_PxD_VALID_BIT))
241 #define PxD_FLAG_MASK     (0xf)
242 #define PxD_FLAG_SHIFT    (4)
243 #define PxD_VALUE_SHIFT   (PFN_PTE_SHIFT-PxD_FLAG_SHIFT)
244 
245 #ifndef __ASSEMBLY__
246 
247 #define PAGE_NONE	__pgprot(_PAGE_PRESENT | _PAGE_USER)
248 #define PAGE_SHARED	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_WRITE)
249 /* Others seem to make this executable, I don't know if that's correct
250    or not.  The stack is mapped this way though so this is necessary
251    in the short term - dhd@linuxcare.com, 2000-08-08 */
252 #define PAGE_READONLY	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ)
253 #define PAGE_WRITEONLY  __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_WRITE)
254 #define PAGE_EXECREAD   __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_EXEC)
255 #define PAGE_COPY       PAGE_EXECREAD
256 #define PAGE_RWX        __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_WRITE | _PAGE_EXEC)
257 #define PAGE_KERNEL	__pgprot(_PAGE_KERNEL)
258 #define PAGE_KERNEL_EXEC	__pgprot(_PAGE_KERNEL_EXEC)
259 #define PAGE_KERNEL_RWX	__pgprot(_PAGE_KERNEL_RWX)
260 #define PAGE_KERNEL_RO	__pgprot(_PAGE_KERNEL_RO)
261 #define PAGE_KERNEL_UNC	__pgprot(_PAGE_KERNEL | _PAGE_NO_CACHE)
262 #define PAGE_GATEWAY    __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_GATEWAY| _PAGE_READ)
263 
264 
265 /*
266  * We could have an execute only page using "gateway - promote to priv
267  * level 3", but that is kind of silly. So, the way things are defined
268  * now, we must always have read permission for pages with execute
269  * permission. For the fun of it we'll go ahead and support write only
270  * pages.
271  */
272 
273 	 /*xwr*/
274 #define __P000  PAGE_NONE
275 #define __P001  PAGE_READONLY
276 #define __P010  __P000 /* copy on write */
277 #define __P011  __P001 /* copy on write */
278 #define __P100  PAGE_EXECREAD
279 #define __P101  PAGE_EXECREAD
280 #define __P110  __P100 /* copy on write */
281 #define __P111  __P101 /* copy on write */
282 
283 #define __S000  PAGE_NONE
284 #define __S001  PAGE_READONLY
285 #define __S010  PAGE_WRITEONLY
286 #define __S011  PAGE_SHARED
287 #define __S100  PAGE_EXECREAD
288 #define __S101  PAGE_EXECREAD
289 #define __S110  PAGE_RWX
290 #define __S111  PAGE_RWX
291 
292 
293 extern pgd_t swapper_pg_dir[]; /* declared in init_task.c */
294 
295 /* initial page tables for 0-8MB for kernel */
296 
297 extern pte_t pg0[];
298 
299 /* zero page used for uninitialized stuff */
300 
301 extern unsigned long *empty_zero_page;
302 
303 /*
304  * ZERO_PAGE is a global shared page that is always zero: used
305  * for zero-mapped memory areas etc..
306  */
307 
308 #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
309 
310 #define pte_none(x)     (pte_val(x) == 0)
311 #define pte_present(x)	(pte_val(x) & _PAGE_PRESENT)
312 #define pte_user(x)	(pte_val(x) & _PAGE_USER)
313 #define pte_clear(mm, addr, xp)  set_pte_at(mm, addr, xp, __pte(0))
314 
315 #define pmd_flag(x)	(pmd_val(x) & PxD_FLAG_MASK)
316 #define pmd_address(x)	((unsigned long)(pmd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
317 #define pud_flag(x)	(pud_val(x) & PxD_FLAG_MASK)
318 #define pud_address(x)	((unsigned long)(pud_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
319 #define pgd_flag(x)	(pgd_val(x) & PxD_FLAG_MASK)
320 #define pgd_address(x)	((unsigned long)(pgd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
321 
322 #define pmd_none(x)	(!pmd_val(x))
323 #define pmd_bad(x)	(!(pmd_flag(x) & PxD_FLAG_VALID))
324 #define pmd_present(x)	(pmd_flag(x) & PxD_FLAG_PRESENT)
325 static inline void pmd_clear(pmd_t *pmd) {
326 		set_pmd(pmd,  __pmd(0));
327 }
328 
329 
330 
331 #if CONFIG_PGTABLE_LEVELS == 3
332 #define pud_pgtable(pud) ((pmd_t *) __va(pud_address(pud)))
333 #define pud_page(pud)	virt_to_page((void *)pud_pgtable(pud))
334 
335 /* For 64 bit we have three level tables */
336 
337 #define pud_none(x)     (!pud_val(x))
338 #define pud_bad(x)      (!(pud_flag(x) & PxD_FLAG_VALID))
339 #define pud_present(x)  (pud_flag(x) & PxD_FLAG_PRESENT)
340 static inline void pud_clear(pud_t *pud) {
341 	set_pud(pud, __pud(0));
342 }
343 #endif
344 
345 /*
346  * The following only work if pte_present() is true.
347  * Undefined behaviour if not..
348  */
349 static inline int pte_dirty(pte_t pte)		{ return pte_val(pte) & _PAGE_DIRTY; }
350 static inline int pte_young(pte_t pte)		{ return pte_val(pte) & _PAGE_ACCESSED; }
351 static inline int pte_write(pte_t pte)		{ return pte_val(pte) & _PAGE_WRITE; }
352 static inline int pte_special(pte_t pte)	{ return pte_val(pte) & _PAGE_SPECIAL; }
353 
354 static inline pte_t pte_mkclean(pte_t pte)	{ pte_val(pte) &= ~_PAGE_DIRTY; return pte; }
355 static inline pte_t pte_mkold(pte_t pte)	{ pte_val(pte) &= ~_PAGE_ACCESSED; return pte; }
356 static inline pte_t pte_wrprotect(pte_t pte)	{ pte_val(pte) &= ~_PAGE_WRITE; return pte; }
357 static inline pte_t pte_mkdirty(pte_t pte)	{ pte_val(pte) |= _PAGE_DIRTY; return pte; }
358 static inline pte_t pte_mkyoung(pte_t pte)	{ pte_val(pte) |= _PAGE_ACCESSED; return pte; }
359 static inline pte_t pte_mkwrite(pte_t pte)	{ pte_val(pte) |= _PAGE_WRITE; return pte; }
360 static inline pte_t pte_mkspecial(pte_t pte)	{ pte_val(pte) |= _PAGE_SPECIAL; return pte; }
361 
362 /*
363  * Huge pte definitions.
364  */
365 #ifdef CONFIG_HUGETLB_PAGE
366 #define pte_huge(pte)           (pte_val(pte) & _PAGE_HUGE)
367 #define pte_mkhuge(pte)         (__pte(pte_val(pte) | \
368 				 (parisc_requires_coherency() ? 0 : _PAGE_HUGE)))
369 #else
370 #define pte_huge(pte)           (0)
371 #define pte_mkhuge(pte)         (pte)
372 #endif
373 
374 
375 /*
376  * Conversion functions: convert a page and protection to a page entry,
377  * and a page entry and page directory to the page they refer to.
378  */
379 #define __mk_pte(addr,pgprot) \
380 ({									\
381 	pte_t __pte;							\
382 									\
383 	pte_val(__pte) = ((((addr)>>PAGE_SHIFT)<<PFN_PTE_SHIFT) + pgprot_val(pgprot));	\
384 									\
385 	__pte;								\
386 })
387 
388 #define mk_pte(page, pgprot)	pfn_pte(page_to_pfn(page), (pgprot))
389 
390 static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot)
391 {
392 	pte_t pte;
393 	pte_val(pte) = (pfn << PFN_PTE_SHIFT) | pgprot_val(pgprot);
394 	return pte;
395 }
396 
397 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
398 { pte_val(pte) = (pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot); return pte; }
399 
400 /* Permanent address of a page.  On parisc we don't have highmem. */
401 
402 #define pte_pfn(x)		(pte_val(x) >> PFN_PTE_SHIFT)
403 
404 #define pte_page(pte)		(pfn_to_page(pte_pfn(pte)))
405 
406 static inline unsigned long pmd_page_vaddr(pmd_t pmd)
407 {
408 	return ((unsigned long) __va(pmd_address(pmd)));
409 }
410 
411 #define pmd_pfn(pmd)	(pmd_address(pmd) >> PAGE_SHIFT)
412 #define __pmd_page(pmd) ((unsigned long) __va(pmd_address(pmd)))
413 #define pmd_page(pmd)	virt_to_page((void *)__pmd_page(pmd))
414 
415 /* Find an entry in the second-level page table.. */
416 
417 extern void paging_init (void);
418 
419 /* Used for deferring calls to flush_dcache_page() */
420 
421 #define PG_dcache_dirty         PG_arch_1
422 
423 #define update_mmu_cache(vms,addr,ptep) __update_cache(*ptep)
424 
425 /* Encode and de-code a swap entry */
426 
427 #define __swp_type(x)                     ((x).val & 0x1f)
428 #define __swp_offset(x)                   ( (((x).val >> 6) &  0x7) | \
429 					  (((x).val >> 8) & ~0x7) )
430 #define __swp_entry(type, offset)         ((swp_entry_t) { (type) | \
431 					    ((offset &  0x7) << 6) | \
432 					    ((offset & ~0x7) << 8) })
433 #define __pte_to_swp_entry(pte)		((swp_entry_t) { pte_val(pte) })
434 #define __swp_entry_to_pte(x)		((pte_t) { (x).val })
435 
436 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
437 {
438 	pte_t pte;
439 
440 	if (!pte_young(*ptep))
441 		return 0;
442 
443 	pte = *ptep;
444 	if (!pte_young(pte)) {
445 		return 0;
446 	}
447 	set_pte_at(vma->vm_mm, addr, ptep, pte_mkold(pte));
448 	return 1;
449 }
450 
451 struct mm_struct;
452 static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
453 {
454 	pte_t old_pte;
455 
456 	old_pte = *ptep;
457 	set_pte_at(mm, addr, ptep, __pte(0));
458 
459 	return old_pte;
460 }
461 
462 static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
463 {
464 	set_pte_at(mm, addr, ptep, pte_wrprotect(*ptep));
465 }
466 
467 #define pte_same(A,B)	(pte_val(A) == pte_val(B))
468 
469 struct seq_file;
470 extern void arch_report_meminfo(struct seq_file *m);
471 
472 #endif /* !__ASSEMBLY__ */
473 
474 
475 /* TLB page size encoding - see table 3-1 in parisc20.pdf */
476 #define _PAGE_SIZE_ENCODING_4K		0
477 #define _PAGE_SIZE_ENCODING_16K		1
478 #define _PAGE_SIZE_ENCODING_64K		2
479 #define _PAGE_SIZE_ENCODING_256K	3
480 #define _PAGE_SIZE_ENCODING_1M		4
481 #define _PAGE_SIZE_ENCODING_4M		5
482 #define _PAGE_SIZE_ENCODING_16M		6
483 #define _PAGE_SIZE_ENCODING_64M		7
484 
485 #if defined(CONFIG_PARISC_PAGE_SIZE_4KB)
486 # define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_4K
487 #elif defined(CONFIG_PARISC_PAGE_SIZE_16KB)
488 # define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_16K
489 #elif defined(CONFIG_PARISC_PAGE_SIZE_64KB)
490 # define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_64K
491 #endif
492 
493 
494 #define pgprot_noncached(prot) __pgprot(pgprot_val(prot) | _PAGE_NO_CACHE)
495 
496 /* We provide our own get_unmapped_area to provide cache coherency */
497 
498 #define HAVE_ARCH_UNMAPPED_AREA
499 #define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
500 
501 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
502 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
503 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
504 #define __HAVE_ARCH_PTE_SAME
505 
506 #endif /* _PARISC_PGTABLE_H */
507